SSTACK 	SEGMENT STACK
	DB 100 DUP(?)
SSTACK	ENDS
CSEG	SEGMENT
ASSUME	CS:CSEG,SS:SSTACK
START:	XOR AX,AX
	MOV DX,0273H
	MOV AL,10000010B
	OUT DX,AL
NEXT1:	MOV DX,0271H
	IN AL,DX
	ADD AL,0
	JZ NEXT2
	MOV DX,0270H
	OUT DX,AL
	JMP NEXT1
NEXT2: 	MOV DX,0270H
	MOV AL,00H
	OUT DX,AL
	CALL DELAY
	MOV AL,0FFH
	OUT DX,AL
	CALL DELAY
	MOV AL,0FFH
	OUT DX,AL
	CALL DELAY
	JMP NEXT1
	RET
DELAY:	MOV BX,0050H
LT1:	MOV CX,0FFFFH
LT2:	LOOP LT2
	DEC BX
	JNZ LT1
	RET
CSEG ENDS
END START
